/// <summary>
/// Returns all hexes around current hex which meet provided criteria
/// </summary>
/// <param name="size">Board dimensions</param>
/// <param name="origin">Current hex coordinates</param>
/// <param name="predicate">Search criteria</param>
/// <returns></returns>
public IEnumerable <IntPoint> GetArea(IntSize size, IntPoint origin, Func <IntPoint, bool> predicate)
{
if (false == predicate(origin))
{
yield break;
}
int idx = 0;
var points = new List <IntPoint>();
points.Add(origin);
do
{
IntPoint p = points[idx];
yield return(p);
foreach (var point in GetNeighbours(size, p).Where(predicate))
{
if (points.IndexOf(point) < 0)
{
points.Add(point);
}
}
idx++;
}while (idx < points.Count);
}
/// <summary>
/// Returns adjacent hex
/// </summary>
/// <param name="size">Board dimensions</param>
/// <param name="origin">Current hex coordinates</param>
/// <param name="dir">Direction</param>
public IntPoint?GetNextHex(IntSize size, IntPoint origin, HexDirection dir)
{
if (IsHorizontal)
{
return(GetNextHexHorizontal(size, origin, dir));
}
return(GetNextHexVertical(size, origin, dir));
}
/// <summary>
/// Returns all adjacent hexes
/// </summary>
/// <param name="size">Board dimensions</param>
/// <param name="origin">Current hex coordinates</param>
public IEnumerable <IntPoint> GetNeighbours(IntSize size, IntPoint origin)
{
for (int index = 0; index < _directions.Length; index++)
{
HexDirection dir = _directions[index];
var point = GetNextHex(size, origin, dir);
if (point.HasValue)
{
yield return(point.Value);
}
}
}
/// <summary>
/// Returns all in the requested direction from current hex to board border
/// </summary>
/// <param name="size">Board dimensions</param>
/// <param name="origin">Current hex coordinates</param>
/// <param name="dir">Direction</param>
public IEnumerable <IntPoint> GetRay(IntSize size, IntPoint origin, HexDirection dir)
{
IntPoint?next;
do
{
next = GetNextHex(size, origin, dir);
if (next != null)
{
yield return(next.Value);
origin = next.Value;
}
}while (next != null);
}
private IntPoint?GetNextHexVertical(IntSize size, IntPoint origin, HexDirection dir)
{
if (dir == HexDirection.Up || dir == HexDirection.Down)
{
return(null);
}
int rows = size.Height;
int columns = size.Width;
int row = origin.X;
int column = origin.Y;
if (row == 0 && (dir == HexDirection.UpRight || dir == HexDirection.UpLeft))
{
return(null);
}
if (row == rows - 1 && (dir == HexDirection.DownRight || dir == HexDirection.DownLeft))
{
return(null);
}
if (column == 0 && dir == HexDirection.Left)
{
return(null);
}
if (column == columns - 1 && dir == HexDirection.Right)
{
return(null);
}
bool evenRow = row % 2 == 0;
if (evenRow && column == 0 && (dir == HexDirection.UpLeft || dir == HexDirection.DownLeft))
{
return(null);
}
if (evenRow == false && column == columns - 1 && (dir == HexDirection.UpRight || dir == HexDirection.DownRight))
{
return(null);
}
switch (dir)
{
case HexDirection.Right:
column++;
break;
case HexDirection.Left:
column--;
break;
case HexDirection.UpRight:
if (evenRow == false)
{
column++;
}
row--;
break;
case HexDirection.DownRight:
if (evenRow == false)
{
column++;
}
row++;
break;
case HexDirection.UpLeft:
if (evenRow)
{
column--;
}
row--;
break;
case HexDirection.DownLeft:
if (evenRow)
{
column--;
}
row++;
break;
}
if (row >= 0 && row < rows && column >= 0 && column <= columns)
{
return(new IntPoint(row, column));
}
return(null);
}
public bool IsNeigbour(IntPoint neighbour, IntSize size, IntPoint origin)
{
var nb = GetNeighbours(size, origin);
return(nb.Any(p => p == neighbour));
}
